JP5963201B2 - Engine intake air amount control device - Google Patents

Description

  In the present invention, a valve guide hole and a metering hole that opens on the inner surface of the valve guide hole and through which the intake air of the engine passes are formed in the control base. A control valve for opening and closing the metering hole is slidably and non-rotatably fitted, and a screw mechanism is provided on the control valve so that the output shaft of the electric motor attached to the control base can be rotated forward and backward. A slide piece that is non-rotatably accommodated in the hollow portion of the control valve and abuts against a contact portion provided at one axial end of the control valve; and the output shaft And a screw shaft that is screwed into a screw hole provided in the slide piece along the sliding direction of the control valve, and the contact between the slide piece and the control valve. Was under compression coil spring held in the contact position between the sliding piece, an improvement in intake air amount control device for an engine.

  Such an intake control device for an engine is already known as disclosed in Patent Document 1 below.

JP 2009-114997 A

  In the engine intake air amount control device described in Patent Document 1, the screw hole of the screw mechanism is provided as a through hole in the slide piece, and chips generated during processing of the screw hole are discharged from the tip opening of the screw hole. Yes. However, in such a case, during operation of the engine, dust such as soot contained in the backfire gas enters the screw hole from the opening of the tip, and enters the screw hole and the screwed portion of the screw shaft, thereby smoothing the screw mechanism. May interfere with proper operation. Therefore, in the above-mentioned Patent Document 1, a pair of spring pins that cross the screw hole is attached to the tip of the slide piece, and grease that seals the screw hole is filled between them. The number of parts is large, and the assembly is not good.

  The present invention has been made in view of such circumstances, and it is easy to discharge chips from the screw holes of the screw mechanism, and also allows dust to enter the screw holes without increasing the number of parts and the number of assembly steps. It is an object of the present invention to provide an intake air amount control device for an engine, which can prevent the screw mechanism and maintain the operation of the screw mechanism at all times.

  In order to achieve the above object, the present invention forms a valve guide hole in the control base and a metering hole that opens on the inner surface of the valve guide hole and through which the intake air of the engine passes, A control valve that opens and closes the metering hole is fitted in the valve guide hole so as to be slidable and non-rotatable. A forward / reverse rotation of an electric motor attached to the control base body is driven to open and close the control valve. The output shaft is connected via a screw mechanism, and the screw mechanism is non-rotatably accommodated in the hollow portion of the control valve and contacts a contact portion provided at one axial end portion of the control valve. A slide piece that is in contact with a screw shaft that is connected to the output shaft and is screwed into a screw hole provided in the slide piece along a sliding direction of the control valve. In an intake air amount control device for an engine in which a coil spring for holding the contact portion in a contact position with the slide piece is contracted between control valves, the screw hole provided in the slide piece is provided with a dead end portion. A lateral hole that opens the screw hole to the outer peripheral surface of the slide piece in the vicinity of the dead end, and the coil spring is disposed so as to surround the outer periphery of the slide piece. A tightly wound portion whose end is supported by the slide piece while fitting a coil spring to the outer peripheral surface of the slide piece so as to close the lateral hole, and the control valve having a larger diameter than the tightly wound portion The first feature is that it is constituted by a spring portion having a large-diameter end portion supported by the. The contact portion of the control valve corresponds to a front end wall 12c of the control valve 12 in an embodiment of the present invention described later.

  According to the present invention, in addition to the first feature, the slide piece includes a dead end portion, a pressing portion that contacts the contact portion of the control valve, and one end of the coil spring on the back side of the pressing portion. The control valve is configured as a single part integrally including a first spring seat for supporting the control valve, and the control valve is disposed at the contact portion and the other axial end of the control valve. A second spring seat for supporting the end is integrally formed as a single part, and one side surface of the control valve is provided with an open surface for accommodating the slide piece and the coil spring in the hollow portion; A second feature is that the slide piece is provided with a pair of coaxial holes that are open on opposite side surfaces of the outer periphery and parallel to the open surface. In addition, the said press part respond | corresponds to the closed end wall 27b of the slide piece 27 in embodiment of this invention mentioned later.

  Furthermore, in addition to the first or second feature, the present invention further includes a third feature that restricts the fully open or fully closed position, which is the reference position of the control valve, by bringing the tip of the screw shaft into contact with the dead end portion. It is characterized by.

  According to the first feature of the present invention, the screw hole provided in the slide piece is formed in a bag shape having a dead end portion, and the lateral hole that opens the screw hole to the outer peripheral surface of the slide piece in the vicinity of the dead end portion is formed. Since it is provided, the chips generated during the machining of the screw hole can be discharged from the lateral hole. In addition, a coil spring that holds the contact portion in a contact position with the slide piece is disposed so as to surround the outer periphery of the slide piece, and the coil spring is disposed on the outer periphery of the slide piece so as to close the lateral hole. Since it is composed of a tightly wound portion whose end is supported on the slide piece while being fitted to the surface, and a spring portion having a larger diameter than this tightly wound portion and supported by the control valve. The large diameter end of the coil spring stabilizes the position of the coil spring in the control valve, and the tightly wound portion of the coil spring prevents the dust that has entered the control valve from entering the horizontal hole. Therefore, without increasing the number of parts and assembly man-hours, dust can be prevented from entering the screw hole and screw shaft and the screw mechanism can be operated smoothly. It can be secured.

  According to the second feature of the present invention, the slide piece includes a dead end portion, a pressing portion that contacts the contact portion of the control valve, and a first spring that supports one end of the coil spring on the back side of the pressing portion. And a control valve, which is disposed on the other end in the axial direction of the control valve and supports the other end of the coil spring. Since the air intake control device has a small number of parts, the structure can be simplified. In addition, since an open surface for accommodating the slide piece and the coil spring is provided in the hollow portion of the one side surface of the control valve, the slide piece and the coil spring can be easily assembled into the control valve. Furthermore, since the slide piece is provided with a pair of coaxial lateral holes that are open on opposite sides of the outer periphery of the slide piece, it is possible to improve the dischargeability of chips from the lateral holes when processing the screw holes. In addition, since the horizontal hole is arranged in parallel with the open surface of the control valve, the dust that has entered from the open surface does not go directly to the horizontal hole, and can contribute to prevention of dust intrusion into the screw hole.

  According to the third feature of the present invention, the fully open or fully closed position as the reference position of the control valve is regulated by bringing the tip of the screw shaft into contact with the dead end portion. The reference position of the control valve can be set by using the shaft contact, and no additional member is required for the setting, which can contribute to the simplification of the structure.

1 is a longitudinal side view of an intake air amount control device for an engine according to a first embodiment of the present invention. FIG. 2 is an enlarged sectional view taken along line 2-2 in FIG. 1. FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. FIG. 4 is a view corresponding to FIG. 3 showing a second embodiment of the present invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  First, the description starts with the description of the first embodiment of the present invention shown in FIGS. In FIG. 1, reference numeral 1 denotes a throttle body attached to an engine for a motorcycle, for example, which has an intake passage 2 that communicates with an intake port of the engine at the center and is a butterfly type that opens and closes the intake passage 2. A throttle valve 3 is pivotally supported on the throttle body 1. A support base 4 is integrally formed on the upper side wall of the throttle body 1, and a control base 5 is superimposed on the support base 4 and fastened by a bolt (not shown).

  1 to 3, the control base 5 is formed with a bottomed cylindrical valve guide hole 7. The valve guide hole 7 has a polygonal cross section (see FIG. 3, square in the illustrated example). The lower inner surface of the valve guide hole 7 along the direction of gravity is a control inner surface 8a. The control base 5 is provided with a measuring hole 10 that opens to the control inner side surface 8 a and an inlet hole 11 that opens to the control inner side surface 8 a on the bottom side of the valve guide hole 7 from the measuring hole 10. The measuring hole 10 has a long hole shape whose long diameter is arranged along the axial direction of the valve guide hole 7, and a control valve 12 for opening and closing the measuring hole 10 is slidably fitted in the valve guide hole 7. Is done.

  On the other hand, in the throttle body 1, a bypass upstream passage 14 connecting the intake passage 2 upstream from the throttle valve 3 to the inlet hole 11 and the metering hole 10 are connected to the intake passage 2 downstream from the throttle valve 3. A bypass downstream passage 15 is provided. Between the joint surfaces of the throttle body 1 and the control base 5, there are interposed seal members 16 surrounding the connecting portion between the bypass upstream passage 14 and the inlet hole 11 and the connecting portion between the bypass downstream passage 15 and the measuring hole 10, respectively. Be dressed. Thus, the bypass upstream passage 14, the inlet hole 11, the valve guide hole 7, the metering hole 10 and the bypass downstream passage 15 constitute a bypass 17 that bypasses the throttle valve 3 and is connected to the intake passage 2.

  The control valve 12 is erected from a control wall 12a slidably contacting the control inner side surface 8a of the valve guide hole 7 with the lower side surface as a control outer side surface 8b, and the valve guide hole 7 A pair of side walls 12b, 12b facing both the left and right inner side surfaces, and a front end wall 12c standing up from the front end of the control wall 12a on the bottom side of the valve guide hole 7 and connecting between the front end portions of the side walls 12b, 12b , A control wall 12a and a U-shaped inward flange 12d projecting inward from the rear end of both side walls 12a, 12a, and a box shape having an open surface 12e on the surface opposite to the control wall 12a Therefore, the control valve 12 is slidable in the axial direction in the valve guide hole 7 having a square cross section, but cannot rotate.

  The control base 5 is provided with a motor mounting hole 19 having a diameter larger than that of the valve guide hole 7, which is connected to the opening end of the valve guide hole 7 via a step portion 18, and a stator 20 a of the electric motor 20 is mounted on the control base 5. . At that time, a seal member 21 that is in close contact with the outer peripheral surface of the output shaft 20 b of the electric motor 20 is sandwiched between the front end surface of the stator 20 a and the step portion 18. The output shaft 20b of the electric motor 20 can be rotated forward and backward, and the control valve 12 is connected to the output shaft 20b via a screw mechanism 25.

  The screw mechanism 25 is connected to the control valve 12 via a detent means 26 and is connected to the slide piece 27 that synchronously opens and closes the control valve 12 and the output shaft 20 b of the electric motor 20. The screw shaft 29 is screwed into a screw hole 28 provided along the sliding direction of the control valve 12. The screw hole 28 is formed in a bag shape having a dead end portion 28a. The slide piece 27 is formed on the outer periphery of a cylindrical shaft 27a that passes through the U-shaped inward flange 12d of the control valve 12 and is disposed in the control valve 12, and a closed end wall 27b at the front end of the cylindrical shaft 27a. The cylindrical shaft 27a is provided with a bag-like screw hole 28 into which the screw shaft 29 is screwed. The cylindrical shaft 27a has a pair of coaxial holes 30 in the vicinity of the dead end portion 28a of the screw hole 28 so that the screw hole 28 is opened to both opposing surfaces on the outer periphery of the cylindrical shaft 27a and parallel to the open surface 12e of the control valve 12. 30 is provided.

  A first spring seat 31 is formed on the inner surface of the outward flange 27c, and a second spring seat 32 is formed on the inner surface of the inward flange 12d. A coil spring 33 is formed between the spring spring seats 31 and 32, respectively. Due to the set load of the coil spring 33, the control valve 12 is urged rearward, that is, toward the electric motor 20 with respect to the slide piece 27, so that the front end wall 12c of the slide piece 27 is in contact with the outward flange 27c. The contact state is maintained. Thereby, the slide piece 27 and the control valve 12 are connected to each other without backlash in the axial direction.

  The coil spring 33 is integrally connected to the tightly wound portion 33a that is fitted to the outer peripheral portion of the cylindrical shaft 27a in which the lateral holes 30 and 30 are bored while being supported by the first spring seat 31. And a cone spring portion 33b having a larger diameter than the tightly wound portion 33a and having a large diameter end portion 33b1 supported by the control valve 12. The tightly wound portion 33a is an outer end of the lateral holes 30 and 30. The opening is closed.

  As shown in FIGS. 2 and 3, the anti-rotation means 26 includes a pressure protrusion 35 that integrally projects from the outer end surface of the closed end wall 27 b with the flange 27 c of the slide piece 27, and the control valve 12. A pressure receiving projection 36 is provided on the inner surface of the front end wall 12c so as to stand up from the inner surface of the wall 12a. The pressure protrusion 35 includes first and second pressure portions 35a having a pair of pressure surfaces 35a1 and 35b1 arranged in a V shape so as to sandwich the pressure receiving protrusion 36 along the rotation direction of the screw shaft 29. 35b is provided, and the opening angle θ between the pair of pressure surfaces 35a1 and 35b1 arranged in the V shape is set to 90 ° or more. Thus, the pressing surfaces 35a1 and 25b1 of the first and second pressing portions 35a and 35b facing each other can be easily processed by the end mill.

  On the other hand, the pressure receiving projection 36 is provided with convex first and second pressure receiving portions 36a, 36b facing the pressure surfaces 35a1, 35b1, respectively.

  Next, the operation of the first embodiment will be described.

  When the throttle valve 3 is fully closed, an electronic control unit (not shown) starts up the engine based on information on the engine operating conditions such as throttle valve opening, engine intake negative pressure, intake air temperature, engine temperature, and engine speed. The output shaft 20b of the electric motor 20 is controlled by controlling the energization of the electric motor 20 in order to obtain the optimum opening of the control valve 12 corresponding to the engine operating conditions such as during fast idling, normal idling, and engine braking. Is rotated forward or reverse. When the output shaft 20b rotates or reversely rotates, the rotation is transmitted to the control valve 12 via the slide piece 27 while being decelerated by the screw mechanism. The opening area to the valve guide hole 7 can be finely adjusted. Thus, the intake air amount of the engine flowing through the bypass 17 is finely controlled, and it is possible to cope with engine start, fast idling, normal idling, engine braking, and the like.

  By the way, as shown in FIG. 3A, when the output shaft 20b of the electric motor 20 is rotated forward, the forward rotation torque T1 of the output shaft 20b is applied to the slide piece 27 via the friction between the screw shaft 29 and the screw hole 28. Then, the pressurizing surface 35a1 of the first pressurizing portion 35a presses the first pressure receiving portion 36a obliquely against the control inner surface 8a of the valve guide hole 7. Accordingly, the pressing force F applied to the first pressure receiving portion 36a is decomposed into a first component force perpendicular to the control inner surface 8a and a second component force F2 parallel to the control inner surface 8a, and the first component force F1. The control valve 12 is pressed against the control inner surface 8a, and the second component force F2 presses the control valve 12 against one inner surface of the valve guide hole 7. As shown in FIG. 3B, when the output shaft 20b of the electric motor 20 is reversely rotated, the reverse rotation torque T2 of the output shaft 20b is transmitted to the slide piece 27 via the friction between the screw shaft 29 and the screw hole 28. The pressurizing surface 35b1 of the second pressurizing portion 35b presses the second pressure receiving portion 36b against the control inner side surface 8a of the valve guide hole 7 in an oblique direction opposite to the previous time. Therefore, the pressing force F applied to the second pressure receiving portion 36b is divided into a first component force perpendicular to the control inner surface 8a and a second component force F2 parallel to the control inner surface 8a, and the first component force F1 is controlled. The valve 12 is pressed against the control inner surface 8a, and the second component force F2 presses the control valve 12 against the other inner surface of the valve guide hole 7.

  Thus, since the control valve 12 is pressed against the control inner surface 8a side of the valve guide hole 7 by the first component force F1 in both the forward rotation and the reverse rotation of the output shaft 20b, the control outer surface 8b. Can be brought into close contact with the control inner surface 8 a of the valve guide hole 7. That is, a gap can be eliminated from between the control inner side surface 8a and the control outer side surface 8b, and in this state, the control valve 12 opens and closes the measuring hole 10 opened to the control inner side surface 8a. 7 and the control valve 12 can eliminate the leakage of intake air, and therefore, even when the control valve 12 is fully closed or partially opened, an appropriate bypass intake air amount corresponding to the opening is supplied to the engine. be able to. Moreover, the measuring hole 10 opened and closed by the control valve 12 has a long hole shape in which the long diameter is directed in the sliding direction of the control valve 12, so that the effective opening area is finely adjusted according to the sliding of the control valve 12. Can be adjusted.

  In this case, the control valve 12 is simultaneously subjected to a pressing force toward the control inner surface 8a due to gravity and a suction force due to the intake negative pressure of the engine acting on the control outer surface 8b of the control valve 12 from the measuring hole 10, By these, the adhesion force between the control outer side surface 8b and the control inner side surface 8a is further strengthened.

  The screw shaft 29 of the screw mechanism 25 pulls the slide piece 27 rearward, and the tip end portion of the screw mechanism 29 abuts against the dead end portion 28a of the screw hole 28 of the slide piece 27. Is regulated, and the measuring hole 10 is fully opened. This fully open position becomes the reference position of the control valve 12, the closing position of the control valve 12 is determined by the rotation angle of the output shaft 20b of the electric motor 20 from this reference position, and the opening degree of the measuring hole 10 is controlled.

  If the throttle valve 3 is opened, an amount of intake air corresponding to the opening degree is supplied to the engine through the intake passage 2, and the engine moves to the output operation range.

  By the way, the slide piece 27 and the control valve 12 are connected to each other in the axial direction by the coil spring 33, and the control valve 12 can follow the movement of the slide piece 27 in the axial direction without delay.

  In addition, the rotation preventing means 26 for connecting the slide piece 27 and the control valve 12 includes a pressure protrusion 35 that is integrally projected on the outer end surface of the closed end wall 27 b with the flange 27 c of the slide piece 27, and the control valve 12. The pressure receiving projection 36 is provided on the inner surface of the front end wall 12c so as to stand up from the inner surface of the control wall 12a. This can contribute to simplification of the structure. In addition, the rotation prevention means 26 can be configured compactly between the front end wall 12c of the control valve 12 and the outer end surface of the closed end wall 27b of the slide piece 27 accommodated in the control valve 12. An increase in the size of the quantity control device can be avoided.

  Further, when the screw hole 28 into which the screw shaft 29 is screwed is machined into the slide piece 27, first, the pilot hole of the screw hole 28 is first formed, and then a pair of coaxial holes 30 so as to cross the lower hole. , 30 is drilled, and then the screw hole is reamed into the lower hole. By doing so, the horizontal holes 30 and 30 cut the burrs (working residue) due to processing, and the screw hole 28 is insufficiently processed. Not only can be surely prevented, but also the chips generated at that time can be smoothly discharged from the horizontal holes 30 and 30, and when the screw hole 28 is washed, the remaining chips are removed by a pair of coaxial Since it can discharge | emit smoothly from the holes 30 and 30, the highly accurate screw hole 28 can be obtained. Further, the dead end portion 28a can be constituted by the bottom portion of the lower hole of the screw hole 28, and the structure can be simplified. In addition, if the horizontal holes 30 and 30 are formed larger in diameter than the lower hole, the cutting effect and discharging effect of the burr can be enhanced.

  Further, a coil spring 33 arranged so as to surround the cylindrical shaft 27a of the slide piece 27 so as to connect the slide piece 27 and the control valve 12 in the axial direction is closed by the slide piece 27 so as to close the lateral holes 30 and 30. The tightly wound portion 33a whose end is supported by the first spring seat 31 of the slide piece 27 while being fitted to the outer peripheral surface of the slide piece 27, and the second spring seat 32 of the control valve 12 having a larger diameter than the tightly wound portion 33a. Since the cone spring portion 33b having the large diameter end portion 33b1 to be supported is configured, the large diameter end portion 33e1 of the coil spring 33 stabilizes the posture of the coil spring 33 in the control valve 12, and the tightly wound portion. 33a can prevent the dust that has entered the control valve 12 from entering the horizontal holes 30 and 30, and the horizontal holes Since 0 and 30 are arranged in parallel with the open surface 12e of the control valve 12, dust entering from the open surface 12e does not go directly to the lateral holes 30 and 30 and contributes to preventing dust from entering the screw hole 28. Can do. Therefore, without increasing the number of parts and assembly man-hours, dust can be prevented from entering the screw hole 28 and the screw shaft 29, and the smooth operation of the screw mechanism 25 can be guaranteed.

  Further, since the tip end of the screw shaft 29 is brought into contact with the dead end portion, the fully open position as the reference position of the control valve is regulated, so that the screw shaft 29 is applied to the dead end portion 28a of the screw hole 28. By utilizing this, the reference position of the control valve 12 can be easily set, and no additional member is required for the setting, which can contribute to simplification of the structure.

  When assembling the intake air amount control device, first, the slide piece 27 fitted with the coil spring 33 is housed in the control valve 12 from the open surface 12e while the coil spring 33 is contracted, and the pressure protrusion of the slide piece 27 is accommodated. 35 is engaged with the pressure receiving projection 36 of the control valve 12, and at the same time, the coil spring 33 is released and the cone spring portion 33 b is supported on the second spring seat 32 of the control valve 12.

  Next, the screw shaft 29 on the electric motor 20 side is screwed into the screw hole 28 of the slide piece 27 to constitute an assembly of the electric motor 20 and the control valve 12. Alternatively, the screw shaft 29 may be first screwed into the screw hole 28 of the slide piece 27, and then the slide piece 27 may be housed in the control valve 12 together with the coil spring 33 from the open surface 12e. In any case, the slide piece 27 and the coil spring 33 can be easily assembled into the control valve 12 by using the open surface 12e of the control valve 12.

  Next, the control valve 12 is fitted into the valve guide hole 7 of the control base 5. At this time, since the open surface 12e of the control valve 12 is closed at the upper surface of the valve guide hole 7, the detachment of the slide piece 27 from the open surface 12e of the control valve 12 can be prevented. No special detachment prevention means is required, so that the assembly can be improved and the structure can be simplified. In addition, the accommodating space in the box-shaped control valve 12 whose upper surface is the open surface 12e has a wide cross section by the amount that the upper surface is the open surface 12e. Therefore, the control valve 12 can be made compact. However, the coil spring 33 and the slide piece 27 can be easily accommodated in the accommodation space.

  Subsequently, after the electric motor 20 is fitted in the motor mounting hole 19 of the control base 5, the electric motor 20 is fastened to the control base 5 with bolts (not shown).

  Moreover, since the control valve 12 and the valve guide hole 7 have a polygonal cross-section, the rotation of the control valve 12 can be prevented without using a rotation prevention means such as a key and a key groove, and the screw mechanism 25 can be stabilized. Actuation can be obtained.

  Next, a second embodiment of the present invention shown in FIG. 4 will be described.

  In the second embodiment, the valve guide hole 7 and the control valve 12 are formed so that the cross-section is an isosceles trapezoid, and the control inner side surface 8a and the control outer side surface 8b are arranged on the lower bottom of each. Except for this, the configuration is the same as that of the previous embodiment. In FIG.

  According to the second embodiment, when the output shaft 20b is rotated forward or backward, any one of the first and second pressure members 35a and 35b is pressed against the corresponding first pressure member 36a or the first pressure member 36b. When the pressure F is applied, the second component force F2 parallel to the control inner surface 8a generated in the first pressure receiving portion 36a or the first pressure receiving portion 36b causes the control valve 12 to move to either the left or right inner surface of the valve guide hole 7. However, since the inner surface of the inner surface is inclined inward, the reaction force toward the control inner surface 8a is generated on the control valve 12 when receiving the second component force F2. As a result, the control outer surface 8b of the control valve 12 is more closely attached to the control inner surface 8a, and the effect of eliminating the gap between the control inner surface 8a and the control outer surface 8b can be enhanced. .

  The present invention is not limited to the above embodiment, and various design changes can be made without departing from the scope of the invention. For example, instead of the electric motor 20, a step motor or other types of motors can be used. Further, the reference position of the control valve 12 when the tip of the screw shaft 29 hits the dead end portion 28a of the screw hole 28 can be set to the fully closed position of the control valve 12. The entire cone spring portion 33b of the coil spring 33 can be formed in a cylindrical shape having the same diameter as the large-diameter end portion 33b1.

5. Control body 7 ... Valve guide hole 10 ... Metering hole 12 ... Control valve 12c ... Contact part (front end wall)
12e ... Open surface 20 ... Electric motor 20b ... Output shaft 25 ... Screw mechanism 27 ... Slide piece 27b ... Pressing part (closed end wall)
28 ... Screw hole 29 ... Screw shaft 30 ... Horizontal hole 31 ... First spring seat 32 ... Second spring seat 33 ... Coil spring 33a ... Close winding part 33b ... Spring part (cone spring part)
33b1 ... Large diameter end

Claims (3)

The control base (5) has a valve guide hole (7) and a metering hole (10) that opens on the inner surface of the valve guide hole (7) and through which the intake air of the engine passes. In the valve guide hole (7), a control valve (12) for opening and closing the measuring hole (10) is slidably and non-rotatably fitted, and the control valve (12) is opened and closed. In order to drive, an output shaft (20b) of the electric motor (20) attached to the control base (5) is connected via a screw mechanism (25), and the screw mechanism (25) A slide piece (27) that is non-rotatably accommodated in a hollow portion of the control valve (12) and abuts a contact portion (12c) provided at one axial end of the control valve (12); and the output shaft (20b), the slide A screw shaft (29) that is screwed into a screw hole (28) provided along the sliding direction of the control valve (12), and the slide piece (27) and the control In the engine intake air amount control device, a coil spring (33) for holding the contact portion (12c) in a contact position with the slide piece (27) is contracted between the valves (12).
The screw hole (28) provided in the slide piece (27) is formed in a bag shape having a dead end portion (28a), and the screw hole (28) is formed in the vicinity of the dead end portion (28a). A lateral hole (30) is provided on the outer peripheral surface of (27),
The coil spring (33) is disposed so as to surround the outer periphery of the slide piece (27), and the coil spring (33) is disposed on the outer periphery of the slide piece (27) so as to close the lateral hole (30). A tightly wound part (33a) whose end is supported by the slide piece (27) while being fitted to the surface, and a large diameter supported by the control valve (12) with a larger diameter than the tightly wound part (33a). An engine intake air amount control device comprising a spring portion (33b) having a radial end portion (33b1). The intake air amount control device for an engine according to claim 1,
The slide piece (27) includes a dead end portion (28a), a pressing portion (27b) that contacts the contact portion (12c) of the control valve (12), and a back side of the pressing portion (27b). The first spring seat (31) that supports one end of the coil spring (33) is integrally formed as a single part, and the control valve (12) is formed of the contact portion (12c) and the contact portion (12c). A second spring seat (32) that is disposed at the other axial end of the control valve (12) and supports the other end of the coil spring (33) is formed as a single part;
One side surface of the control valve (12) is provided with an open surface (12e) for accommodating the slide piece (27) and the coil spring (33) in the hollow portion thereof,
The slide piece (27) is provided with a pair of coaxial holes (30) that are open on opposite sides of the outer periphery of the slide piece (27) and parallel to the open surface (12e). Intake amount control device. The engine intake air amount control device according to claim 1 or 2,
The intake air amount control of the engine is characterized in that the fully open or fully closed position as the reference position of the control valve (12) is regulated by bringing the tip of the screw shaft (29) into contact with the dead end (28a). apparatus.

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